Center-adjustable universal chuck with automatic torsion lock



Feb. 4, 1958 H. E. SLOAN CENTER-ADJUSTABLE UNIVERSAL CHUCK WITHAUTOMATIC TORSION LOCK 2 Sheets-Sheet 1 Filed Aug. 50, 1955 IN V EN TOR.Harry 5 SZOQW H rag T Feb. 4, 1958 2,822,181

H. E. SLOAN CENTER-ADJUSTABLE UNIVERSAL CHUCK WITH AUTOMATIC TORSIONLOCK Filed Aug. 30, 1955 2 Sheets-Sheet 2 Hirer/29V CENTER-ADJUSTABLEUNIVERSAL CHUCK WITH AUTOMATIC TORSION LOCK Harry E. Sloan, Hartford,Conn., assignor to The Cu shman Chuck Company, Hartford, Conrn, acorporation of Connecticut Application August 30, 1955, Serial No.531,457

9 Claims. (Cl. 279-414) This invention relates to chucks in general, andto universal chucks of the center-adjustable type in particular.

Universal chucks of this type are characterized by a chuck aggregatewhich customarily comprises a chuck body with movable work-gripping jawsthereon and scrolltype jaw-operating means therein, and a mountingadapter which is fixedly mounted on a support, such as the power spindleof a lathe or other machine tool, for instance, and on which the chuckaggregate is in turn mounted for center-adjustment thereon. Customarily,the chuck aggregate and mounting adapter, conveniently referred tohereinafter as chuck unit and adapter unit, are held in their assembledrelation by holding screws which exert a clamping force on abuttingsurfaces of these units and have such relative clearance from the latteras to permit relative sliding of these surfaces on each other forcenter-adjustment of the chuck unit on the adapter unit.Center-adjustment of the chuck unit on the adapter unit is customarilyachieved by turning readily accessible radial set screws which arereceived in one unit and bear against a customarily cylindrical surfaceof the other unit. Due to the limited surface engagement areas at a fewwidely spaced places between these set screws and the associated unit,the former offer little resistance to torsional operating stresses inthe chuck unit, and in any event offer insuflicient resistanceeffectively to counteract the turning tendencies of the chuck unit underhigh torsional operating stresses induced therein by certain operationson work held thereby even if these set screws are prohibitivelytightened. Hence, the aforementioned clamping force exerted by theholding screws on the units is customarily relied on to transmit most,if not all, operating stresses, including torsional stresses, from thechuck unit to the adapter unit. While the clamping force exerted by theholding screws on the units is suflicient to transmit most ordinaryoperational stresses from the chuck unit to the adapter unit, thisclamping force is not only poorly suited to transmit torsional stressesin any event because of its unfavorable component with which tocounteract relative turning tendencies between the units under suchstress, but is clearly inadequate to transmit from the chuck unit to theadapter unit even moderately high torsional operating stresses withoutpermitting relative rotary slippage between the units. Such relativeslippage between the units under relatively high torsional stresses inthe chuck unit not only entails rapid wear of the aforementioned setscrews and cooperating cylindrical surface of the associated unit and,consequently, early deterioration of the desired micrometer-likeresponse of the chuck unit to rotation of the set screws forcenter-adjustment of the former on the adapter unit, but in manyinstances destroys the very center-adjustment of the chuck unit, or worktherein, for which the set screws have been set.

It is the primary aim and object of the present invention to haveprovisions in a universal chuck of this type for reliably transmittingeven exceptionally high torsional stresses from the chuck unit to theadapter unit, thereby t Patent ice to eliminate in any event relativerotary slippage between the units under external torsion-inducing forcesand, hence, obviate the aforementioned serious disadvantages ensuingtherefrom.

It is another object of the present invention to have the aforementionedtorsional stress transmitting provisions in a universal chuck of thistype perform without any participation either from the clamping forcebetween the units exerted by the customary holding screws, or from theadjustment-holding force of the customary set screws, thereby to permittightening of the holding screws and set screws to the mere extentrequired for the satisfactory performance of their respectiveunits-clamping and adjustment-holding functions, even when the holdingscrews are to exert no greater clamping force on the units than isrequired for holding the latter in their axially assembled relation sothat these holding screws need not be loosened for a center-adjustmentof the chuck unit on the adapter unit on manipulating the set screwswithout undue effort.

It is a further object of the present invention to embody theaforementioned torsional stress transmitting provisions in a universalchuck of this type by the sole use of entirely conventional parts of thelatter and without the addition of any special part or parts, onslightly changing the conventional operative relation between 1 theseconventional parts, thereby to provide a chuck with this special andhighly advantageous torsional stress transmitting feature at no cost, orat the most at insignificant cost over and above that of a conventionalchuck without this special feature.

Another object of the present invention is to embody the aforementionedtorsional stress transmitting provisions in a universal chuck of thistype by the sole use of one or more of the customary set screws for theadjustment of the chuck unit on the adapter unit, by disposing one ormore of these sets screws relative to the assembled units so that theformer cooperate with the unit engaged thereby wedge-like to lock theunits against relative rotation on the slightest, as well as the mostforceful, relative rotational tendencies between the units.

It is a further object of the present invention to dis pose one or moreof the customary set screws relative to the assembled units of auniversal chuck of this type so that these set screws cooperate with theunit engaged thereby not only wedge-like to lock the units againstrelative rotation on relative rotational tendencies between them, asaforementioned, but also to augment, on arrest by the set screws of theadjusted chuck unit against further movement on the adapter unit, theaxial clamping force exerted by the holding screws on the unitssufiiciently so that the over-all clamping force between these units isfor normal operation of the chuck assuredly adequate to transmit alloperational stresses in the chuck unit, save relatively high torsionalstresses, directly to the adapter unit, thereby to permit tightening ofthe holding screws to such an extent only that they need not be loosenedfor a center-adjustment of the chuck unit on manipulation of the setscrews without undue,

anaemia Fig. 1 .is .a fragmentary .front view .of. anniversal chuckembodying the present invention;

Fig. 2 is an enlarged section through the chuck, takensubstantiallyzonthe line H201. Fig.4;

:Fig.r3.zis:anotherlsectionuthroughz-the ohuelg, taken subzstantially.0114 the.line;3-;.3nof :Fig. 2;

Fig. 4 is a reduced cross section throughvaiuniuersal chuck memhodyi-ngpresent a-inuention in :.a nnodified manner;

Fig. ,-5-;isaa1.reduced ;crossssection throughnatamiversalchuckeembodying. monument-invention in another tmodifled-manner;

Fig.1 6. is.- a -.fragmentaryiilongitudinalsseotiomthrougha universal:chuck aembodying the .present innention, ulIl ;a further: modifiedmanner;

Figs. '6AuandaB arewdiagrammatic wiews illustratingthetrelatineaxialtdispositiomoficertain prominenteelementsofthernodified-chuekmf Eigaaand I -7is-.-a'iragmentary;longitudinalssection .throughaa universalachtuckembodyingnthe presentainuention in-;.still anothermodiiied-manner.

--Referr=ing .-to sthe tdrawinggjand .-mbre ,;particularly :to Figs. 1to 3 thereof, the reference numeral -:10-.clesignates a-universalschuckofathe. centerradiustable type, comprisi-ng-abody 12 with workgrippingjaws M and dawoperatingtmechanismv 1 6, anda-n adapter .disc .18 bymeansof which 'the rchuck ebody avithlits parts 3:4 and :16 is adjustably.mounted. on.thegpoweraspindlerlllnot. a lathe or other machine toolall-Fig. 2-).

The chuck .body.-.12,-.be'ing of -.-usual cylindrical. form, is intits-front. -fiacermt providedwithrequiangularlyaspaced radialguideways-26for the jaws 14,:and-is inaitserearprovided.with..a.ringshaped= recess. 28 .Jeauingthechuck body with arearwardly extending peripheral.sskirt :30 and .aecentral hub .32,i.both.nrrar zgedz concentrically with respect loathe-longitudinal:chu'ck..axis.x-=-x.

.Thejaw-operating mechanism. .cornprises,:-in -.the present instance,.a..conventional-.-scroll disc 34 and (a -pinion.36 of which..the..former' is.recei-ved.=in therear --recess .28 in. theechuckIbody1.2..and.journalled.-.on..thecentralhub 32.thereof. .The .disc.34=.is..at.-its.f10nt providedavith scroll-like ribs orteeth..38..which..mesh with .similarly formed teeth dfluincbacklof the.jaws..14 .and.move-.1he latter toward .andaway them the chnckcentenxxoon rotation of the disc 34 in opposite directions, as willbe readilyunderstood. The disc =34 .is.:at. its. rear; provided with.bevelteethAZihaLareHinmesh with.similar..teeth 44 of .the:pinionfifit-whichnis journalled atsldand 48 in the skirt 3.0. .andM11132, Iespectively,..of the .chucl: .body

12. TIn order to -hold..the,=pinion 36..against axial escape from thechuck body LIL-.thelkewendflfl of .a retainer. pin 52 projects .into a.peripheraLgrooueSd..in..the.:p.inion. 36. The retainer pin'J'SZ. is.received .preferablywitha sliding, fit,.in.a bore SS-inlthe endnf. the.entralhuhfil ofathe chuck body'lz. IAsusual thepinion36.:is..located..within the peripheral. corifines-dhtherihuckbod-y 12 (Fig.2), and is provided -with .a sdclket 62..or .the'recep'tiori of-a suitable tool, such as.an Allen wrench,.forinstance,.with which to' turn 'the .pinion.aiid, .-hence,.thescrolhdiscfi, for operating the .jaws'14.

'In 'thepresent exemplarychuck 10,..theiadapter disc 148, by means ofwhich theichuckis aidinstblymounted on the power spindle "20 of;a'latheas.llreadymentioned, forms also aseparate.butacomplementarywart,of...the chu'ck bodyil12 in"that"itservesfalso .as.a.retainer.for.the scroll"disc34l.to' keep it incooperative relation withlthe jaws."14. To"this erid,"the.chucki'bddy'fl'llis ldirectly mounted onthe adaptefdisc'ISTiQruiiiYersaLadjuStment thereon withindimits in a plane normal to thechuck axis-xx. This is achieved .by mounting.|the.,chuck bodylZ .onthe.adapterjdiscal'fiibymmeanslofea plurality of screws 64,"forinstance,.which...are..thneadedly.receiued' in the end. of "thelskirt30-6f ,the-chuck'..hody ,12,whi-le their heads *70 .are .receivedlin.cornplementarymarts. .of annular recesses 72 in the body skin 30andadaptertdisc ..18..and seated on the complementary bottom parts ofthese recesses, or at least on the bottoms 73 of the recess parts formedin the adapter disc, so as to hold the front face 66 of the latter on anannular shoulder 68 in the body skirt 30 in clamping engagementtherewith, yet with only such force assto permit forced adjustment ofthe chuck body 12 on the adapter disc 18 in a manner to be described. To.thiszerid, the-.drilledi-holes M'i-n the body skirt 3t) which'aresdbsequentlydapped for the reception ":of c-the ethreaded sshanks 27.6:of the -.=.screws .64, may :betcounterbored topprovide -,-the :recessesflilifor the screw heads 70 when the adapter disc l'lfizisawithoitsfront-.facefifi seated fully, .or nearly so, on the. annularshoulder'68'in the body skirt 39. Universal adjustment of the chuckbody:12.m"th,its; jawsr14;and jaw-operating mechanism 16 as a unit U onthe adapter disc 18, on the relatively slidable surfaces 66 and 68 ofthe disc 13 and: body-skirt-30non :theone hand .and the. bottoms :73ofntheyparts ;of- ,the .zreeesses .7.2 .in. the disc .18 .andthe partsof theiscrew-heads ...'70.-seated .thereon..on..the. other hand, .is.limited .byuthe clearances 78 .andHSfil. between thechuclobody.-.-12vand adapter .disc.18. and. by..the clearances 82.between the recesses .72 .:and .the .screw .heads .10 receivedtherein(Fig. .2.)

.The .adapter :.disc 318 11138 also .suitable ,provisions .foritserearwardtattachment..to..the power .spindlelzfl .of the lathe.oraother. :machine tQolZZZ. .ln @the presentexan ple, the rearface.'.84..of the adapter disc..18.is provided with aid-annular recess.86 for thefittedreceptiouof..theIfront endof thepowems indle 20,1,thusaccurately locating {the adapterdisconthe .power. spindle...Eurther,.,the adapter disc ..18. is provided .with .-apluralityofholesfitl fo-r.,.the reception .of .mounting lscrews .Which.are. .threadedly received .in.,-the..power.spindleh20. .Ihe heads. 92,of..the mounting screws. 30 projectinto .ithrough-holes .94. .in. .thechuck .body .12..through which .they..are; accessible from thefrontofthe chuck. (Zheholesfld inthechuckbody 12 .are..sufliciently.lange .to. .admit a ,suitable wrench to the. screw. .heads. 92in .any..adjustediposition of. the chuck unitzllionathe..adap.ter. .disc l8,.;as.wel1..as.to provide suflioient .,cle.a1:anee .from .,these .rscrew,heads to ,permit uniyersaladiustmentof the. chuck unit 11,.on..th'e..adepter discl-18 .withinithe .aforementiouedlimits.

..Received tin .the. rear skirt..3,.0 of the ..chuck. body ,12are.a:plura 4tyin thisinstancei 'four,..equiangularly.spaced set.screws..1tl0-.w;hich ,on being,..turned. in. appropfiatedirectionsreact .with the..adap.ter ,disc.18.Lin..adjusting.,the chuck unit.,U-.on1.the latter into...any one\of..an..infinite nunlbenbtpo'sitions.thereon .zwithin ..t-he limits imposed after referredto s'imply.=as.Thalls, are seated; and. turnable. .in these sockets. (Conveniently,.:each. socket .104 is simply .and-con\teniently ;.formed by...a.machined. bore on-itheconicaLbottom 1115. of which the:.associated. ball10.2..is seated iand..turnahle. Significantly, each ;of...the

balls..102 .has..a.. cutaway .surface 106 which is preferably a machinedfiat, .while -tl1e;adjacent,v end. surface 108. of the. associatedsetiscrew .100. Eissimilarly flat. and;.-preferably.- zaccuratelymachined. .in order-uniformly, to engage the hatsurfaeelfldmn..themdjacentball 102 throughoutits.areain.theifashionshowntinfig. 3.

'.-Whenever .foraany. reason whateuer,:.such. :as wear of any one ormore. ;of..the .-.par-ts.-of;. the instantechuclenit becomes-snecessaryto. re-centenithezzchuekron: the; power p -by dill ing=thechuckunit-M3011 :theiadapter disc .18 xthronghlurnani relation-moi?:thezsetsserewsi lfltl, as

dessribedgmetfimeendssurfaces 10.8.;of .zthe :dalter awill.

remain in full contact with the flats 106-on -the associated balls 102throughout the adjustment as well as thereafter. This is due to the factthat the balls 102, being free to turn in their respective sockets 104and also slide with their flats 106 on the fiat end surfaces 108 of theadjacent set screws 100, will readily adjust themselves to any positionof the chuck unit on the adapter disc within the prescribed limitswithout losing full contact of their flats with the flat end surfaces ofthe adjacent set screws. justment of the chuck unit U on the adapterdisc is accompanied by a slight rotational component motion of the chuckunit, as is the case in most adjustments. In thus achieving unfailingand full surface-to-surface contact between the balls 102 and set screws100 during any adjustment of the chuck unit U on the adapter disc 18 aswell as in any adjusted position of the former on the latter, it standsto reason that the flats 106 on the balls and the fiat end surfaces 108of the set screws are subjected to hardly any wear for a long period oftime which may well extend to the life of the chuck. Furthermore, evenif the flats 106 of the balls 102 and the flat end surfaces 108 of theset screws 100 should show some slight wear due to their sliding on eachother in consequence of numerous adjustments of the chuck unit on theadapter disc, such wear would be substantially uniform throughout theirareas and, hence, not in the least detrimental to further accurateadjustments of the chuck unit and the ability of the balls and setscrews safely and re liably to transmit for an indefinite length of timesuch operational stresses from the chuck unit to the adapter disc whichare not directly transmitted by virtue of their clamping engagement witheach other by the force of the holding screws 64.

The exemplary chuck described so far is in all major respects like orsimilar to one form of chuck shown and described in my aforementionedcopending application Serial No. 518,013 and, hence, forms no part ofthe present invention.

The present invention deals with a unique feature according to which theset screws 100 are so arranged, in sets, that they cooperate with theirassociated balls 102 in locking or wedging the chuck unit U and theadapter disc or unit 18 to each other against relative rotation inopposite directions, respectively, on relative rotational tendenciesbetween these units. To this end, the set screws 100 in the instantexemplary chuck are disposed so that their axes extend on differentsides, respectively, of the chuck axis x-x (Fig. 3). The set screws 100are, furthermore, arranged in sets of which those of each set act inconcert with each other to oppose relative rotation between the units Uand 18. Thus, the set screws 100' constitute one set which cooperatewith their associated balls 102 to lock the units U and 18 to each otheragainst relative rotation on counterclockwise rotational tendencies ofthe chuck unit U relative to the adapter unit 18 or clockwise rotationaltendencies of the adapter unit 18 relative to the chuck unit U (Fig. 3).Conversely, the set screws 100" constitute the other set which cooperatewith their associated balls 102 to lock the units U and 18 to each otheragainst relative rotation on clockwise rotational tendencies of thechuck unit U relative to the adapter unit 18 or on counterclockwiserotational tendencies of the adapter unit 18 relative to the chuck unitU (Fig. 3). Suppose that the chuck unit U, by virtue of torsionalstresses therein induced by a certain operation on gripped work thereon,for instance, tends to turn clockwise relative to the adapter unit 18(Fig. 3) with an over-all force of a certain magnitude, the two setscrews 100" and their associated balls 102 will act in concert tocounteract this force, each set screw and associated ball counteractingone-half of the magnitude of this force, as constituted by thevectors 1. To lock the units U and 18 to each other against clockwiserotation of the chuck This holds true even when adunit relative to theadapter unit under these circumstances, the forces, constituted by thevectors 7, then acting on the 'set screws and their associated balls 102in consequence of their subjection to the turning force of the chuckunit, must be opposed by forces whose vectors 1" are identical butopposed to each other (Fig. 3). In the present instance, the forces,constituted by the vectors 7, with which the set screws 100 and theirassociated balls are wedged against each other are considerably largerthan the turning forces of the chuck unit as constituted by the vectorsf, this being due to the preferential arrangement of these set screws sothat they do not deviate overly much from radial disposition withrespect to the chuck axis x-x. In arranging these set screws so thatthey do not deviate overly much from such radial disposition, the chuckunit U will respond for its center-adjustment on the adapter unit 18 torotation of these set screws in near optimum fashion. Of course, whilenear radial disposition of the set screws 100" is advantageous for theforegoing reason, the deviation of these set screws from radialdisposition must nevertheless be such that their wedging forces asrepresented by the vectors f will, even under exceptionally hightorsional stresses in the chuck unit, never reach a magnitude at whichthese set screws would be stripped from their tapped holes in the chuckunit, or the cylindrical skirt 30 of the latter would crack.

Coming back to the above-described exemplary tendency of the chuck unitU to turn clockwise (Fig. 3) relative to the adapted unit 18, it followsfrom the preceding that the set screws 100" and their associated balls102 act in concert fully to counteract this relative turning tendency ofthe chuck unit in reliable wedge fashion regardless of the magnitude ofthe force which tends to turn the chuck unit clockwise relative to theadapter unit. Conversely, the set screws 100 and their associated balls102 fully counteract in the same fashion any tendencies of the adapterunit 18 to turn counterclockwise (Fig. 3) relative to the chuck unit U,as will be readily understood.

The set screws 100 of the other set and their associated balls 102 will,as already mentioned, cooperate to lock the units U and 18 to each otheragainst relative rotation on counterclockwise rotational tendencies ofthe chuck unit U relative to the adapter unit 18 (Fig; 3) or onclockwise rotational tendencies of the adapter unit 18 relative to thechuck unit U. Suppose that the chuck unit U, by virtue of torsionalstresses therein induced by a certain machining operation on grippedwork thereon, for instance, tends to turn counterclockwise (Fig. 3)relative to the adapter unit 18, the turning forces of the chuck unit tobe counteracted by the set screws 100 and their associated balls 102,and represented by the vectors f1 (Fig. 3), have components, representedby the vectors f2, which act on these set screws and their associatedballs. To look the units U and 18 to each other against counterclockwiserotation of the chuck unit relative to the adapter unit under theseconditions, the forces represented by the vectors f2 and acting on theset screws we and their associated balls 102 must be opposed by forceswhose vectors f3 are identical with the vectors f2 but opposed to thelatter (Fig. 3). In this instance also, the forces, represented by thevectors f3, with which the set screws 100 and their associated balls 102are wedged against each other are considerably larger than the turningforces of the chuck unit as represented by the vectors fl, due to thepreferential arrangement of these set screws so that they do not deviateoverly much from radial disposition with respect to the chuck axis x-x.

Despite the described non-radial disposition of the set screws 100 withrespect to the chuck axis .xx (Fig. 3), they are preferably furtherdisposed so that they lie with their axes in a common plane normal tothe chuck axis .\'-x (Fig. 2). In doing so, there is no likelihood thath ehscnews 19,0 :-vi .il,1,..on-.itheiir rdtatinniterran' adjus mencf;.theq h '.k ui i on ith ,adaptermni JLI n ant th chuck unitjincanyway soias tolbeccm iheuri on th ap er unit, and ,the ,chuckuni will,finsteaidrespnn iit adjustmen t rotationni thes cset scr w-sin .cP-tjimumjfa'shion. ,Itis also preferahlelmar au ca Set screws Irso; thatth ir axes pass .thetchuckexisixfx tequa'l distancestherefmrn IEig-GQ),with flielresul tha the .wedg'ing itorces ijhetween ihese set screws andtheir assoeiatedlhallsglw are adyantageously,alike.

In the de cription .soifandf the ,exernnlaryehuek .of Fig 1 .t0i3 theaxial isposition Qfillle. setscrews .100 has been defined with rferencrto the "chuck axis x,.x insoiariasihejir.ideyiationjromraxial,dispsifion.with..respec tcf hel tt riis .cuneemed (Fig-J3 Lendsuehreferen-ee tojthe chuck a1 tis ,-x x is ,generallyeccura e. du i thesubstantial ,coineidenceror neanc ineidence'in any vent, fif the le nerlaxes .of the .ehuek and adapterunit in -Yiew of the limite aidiusability. of liter/hunk, unit on h apternitof-ithe;instantexemfilarychuck. 1HQW- ever, it is more,accurate,,a,ndj;in the caseo'rwideradinstability of the chuck unit,ongthe adapter unitreven imperative, ,to relate ,fthe axial disposition,of the ..,set screws, to the longitudinal oncmtet-axishtlthe unit whichessn tlcarry the set screws. flhus, fsincethe setscrews 100 in theinstantexernplary chuck 1.0. are carried ,byMthe chuck "uni .Uhtheyvare.arranged so.that their axe wp the longitudinal or center axis 6f; theadapter ,unit 18 ,on differen sides thereof'in any adjusted position of.the chuck unit o n thej 1atter,, in,or,derthat none, ofuthesersetscrews .rnay- .cpmcieivatblya ssurne, aeradial disposition withrespectlto {the 'center axis ,of the adapter unitand, in consequence,fail ,to perform l its designated Hocking ,or Wedging'fuuctiononrelative rotational tendenciesibetween theunits. :(Conyersely,thenadapteir unitrlti would carry the set screws All!) and; the chuckunit U would carry the.ballslllizuinraiorrn of chu k wlli hisiullywithin he purview of the pre entinventionfithe setscrews woul bearranged so that their axes pass the longitudinal or center ,axis .rofthe. chuck pnit on ,differentusides thereof in any adjusted position ofthe latter on ,the -adapter unit.

While ,all ,of the set screws ,of ,thel-exernplaryhchuck ofiFigs. ,l to:3 are..arran ged. to ghave wedge-like cooperation with,theiresso-ciated. balls oni relatiye rotational tendencies,hetweenrtherchuck iand adapter ,nnits, iewer set screws maybe-arrangedin this fashion if thisis desirable, or feasible Thus, the chuckrltl'uin Fig. .4,.ernploying four .se screws .10fla,,the, same.as .the,, chuck,10= (Fig.v 3),

differs. fromuthellatter in-,th at a-Fminimum,nurnhenofset screws,namely, two,,forluckingeither unit ,to vthe other unit ,against,relativerotation .in opposite directions, are arranged .to havewedge-.likecooperationwith their a s ciatedhalls .102a on relativerotationalltendencies ,hetweenqthewunits. Th 1,1s,;the;set screws.lllliaflearried again y w yofiexamplein the chuck unitUj, mayhedisposedradi lly ofcthe center-laxisx' of. ,theilatterr southatvthewillunotucooperate ineffective wedgeelike fashionwith their associatedballs 102a to ;O PP,QSB pO W l'ful relative rotationaltendenciesobetween. .therunit s, .eyeniithe, chuck unit U were adjustedon the ,adaplterflunitnlsfiso that their. respec iv longitudinalencenteriaxes vwerelaterally spaced ,from each other atthe.permissiblemaximum. However, the remaining. set screws 190a, arevdisposed so that their axes passthe longitudinal or center axis of theadaptenunitldfi sidewisetthereof, preferably atrequal distances,therefrom. \More particularly, the isetnscrew 100a" is, so arrangedvthat it -'..w,ill wedge with its, associated ball 102a and lock bothunits U and 18" to each other on (counterclockwise. rotational -.-teud ni :Qf the chuck-.lmit relative, tolthei adapter nn-ituor ion .ClQCkwiserotationalten encies of the a apter t nitxelat-iue. to the chuckimit.Conversely, he ,set screw, lfllla' is so warranged thatitJwillwedgetwith'itsassociated ball 102a anddochboth units U" and 18' to eachother on clock seem-mi wise, rotational tendencies of the chuckmnitrelative toihe adaptenunit oron;conmerclockwisegrotationaltendencies ofthqadapter-unib relative to thechuc'k unit.

"The described set screw arrangernent-yin the chuck'fl) of-'F ig.-4is-entireIy feasibIe 'where-a singlewet screw and itsassociated-ball-;are adequate safely-to'counteract themaximum-*possi-hle or :expected rotational tendencies of one"unit-relative "tothe otherunit in "one direction or rotationaltendencies Qfjlike 1 magnitude of the other'unit relative-to the oneunitin thempposite 'rlirection. "Also, while the setscrews a" and IOQawith their'wedgelike -reaction -withthe adjacent halls 102a 'on'relative rotational-tendencieshetweenjtheunits ere-showrfinhig.4*in-substant 3 ;ly diametrically pgposed-fdiepo'sition, they mayohviously be -arrangedinextflo each other without aifecting theirdescribed :funetioningjn'any 'way. {It is also fully-Within: the-purview :of the -present invention to have only-one -or niore1of itheset'screws ofthe ohu'ck arranged :to cooperate with their associatedjballs in wedgedike fashion in order to lock ---'the units y-againstrelative grota'tion on--rotational tendencies of one-*urlit-in onedirection relative to the other unit or on rotational tendencie of "theother unit ;-inthe opposite direction relative to the'one' unit."Phusfif the thuck 'll)inFig.-4, forinetance, "is in itsusual-application 4 subjected only to clockwise rotational'tendenciesgot its 4 chuck unit U'---rela-' tiv e to, its: adapter unit-'1:8',ithe-single set ,screw 1410a mayiserve-to eooperate wedgelikewithits' associated hall 102a and; "lock -fthe-units to each other-againstrelative rotation under these circumstances, -while-the remaining set-serews may be arranged radially ,of-the longitudinal orcenter axisx' of the-chuck-urlitj'lil'.

'While"in-theforms of-the'chuck described-so-farcand shown in Figs. 1 to3 and Fig. 4, re spectively,'the,,set screws cooperate "with balls, orequivalent 'r'ollers, the set :screws may "also -cooperate directlyWith-the .unit which-does not carry ithern, -as-demonstratedby ,anexemplar-y chuck IZO-in'FigxS. This chuck may in all respects be likethe described ,chuck '10 (Fig. '13:), exeept---t-hat the -set screws 122in the chuck unit 1124 cooperate directly with peripheral portions 126dithe adapter-unit'iZS. I-n the present exarnple, all ofthe set screws122 are arranged so 'that their ,axes pass "the longitudinal-orcenter-ax-is-x of the adapter ;unit 128 on ditferent-sides-thereof,with-the-result-that'all set screws react wedge-likewith the adjacentperipheral portionslZfi of the adapter unit -123--and* lock 'bo'th units124 and 128 to eachother :againstrelative-rotation on relativerotational tendencies between the -un'its. "Thusythe set screws 122cooperate "wedge-like --with the adjacent --peripheral portions 126 of-'the-adapted unit to lock bothunits against relative -rotation oncounterclockwise rotational tendencies of the chuck unit' -124 relativeto the adapter unit 128 or:on-clockwiserotational tendencies of theadapter i unit'relative to the chu'clcunit. ConverselY; the' set screws122" -cooperate wedge-like with thea'djacent peripheral portions 126-01?the-adapter unit to'lock both onits" against relative .-rota-tion -onclockwise -rotationaltendencies of the ;.chuck unit 124 relative to thew adapter unit-128 or -on.;counterclockwise:rotational tendenciesGrebe=adaptet may automatically 1 lac/controlled to-the end that thisclamping iforce. isiconsi'derably"reduced inmagnitude-"for adjustment:-ot 'the ehuck unit em the adapter unit and is restored to itsfull--magnitude -after such-adjustment is concluded, all in' -response --tomanipulation of the set screws and without' in'any'way 'manipulating'the' holding screws 64. To this-end,'the set-screws 1 00, whichfor the-aehievement of the described interlock of the chuck and "adapter unitson relative rotational tendencies "be- (tween these :units .extend .withtheir taxes ,on-dilierent sides of the longitudinal or center axis-ofthe adapter unit in any adjusted position of the chuck unit on thelatter as shown in Fig. 3, are further disposed so that their axes arealso inclined to the longitudinal or center axis of the chuck unit U asshown in Fig. 6. The axial disposition of each set screw 100 relative tothe longitudinal or center axes of both units is illustrateddiagrammatically in Fig. 6A and 6B, in which these axes are designatedby the reference numeral x' and for the sake of simplicity showncoincident with each other, although these parallel axes may laterallybe spaced from each other as earlier explained. Thus, Fig. 6A shows aset screw 100 vertically beneath the axis x, as seen from the side inFig. 6B, and the perspective illustration of this set screw in Fig. 6Aindicates the inclined disposition of the latter as also shown in Figs.6 and 6B. The further disposition of this set screw 100 so that its axisX passes the axis x'" on one side thereof is diagrammaticallyillustrated in Fig. 6A. Hence, while the axis X of the set screw doesnot pass through the axis x' and, hence, does not form an angle with thelatter, a plane P in which the screw axis X lies and which extendstransversely of the axis x', forms with the latter an acute angle A asshown in Fig. 6B, the plane P being in this figure viewed edgewise and,hence, represented by a single dot-anddash line which is coincident withthe screw axis X. In thus arranging the set screw 100 to bring about theex plained angle formation A (Fig. 6B), the same will on its inwarddrive exert on the adapter unit 18 and chuck unit U reactive forces Rand R (Fig. 6) which have reactive components F1 and F2 whose opposedvectors extend in planes normal to the unit axes and, hence, constituteforces, called adjustment forces, which cooperate to cause movement ofthe chuck unit on the adapter unit for adjustment of the former on thelatter, and further reactive components F3 and F4 whose opposed vectorsextend parallel to the unit axes and, hence, constitute forces, calledbinding forces, which cooperate to clamp the chuck unit to the adapterunit through intermediation of the holding screws 64.

Since in the preferred use of the chuck the units U and 18 remainclamped together with some force by the holding screws 64 even when anyor all set screws 100 should be loosened for an adjustment of the chuckunit, it being contemplated ordinarily not to loosen the holding screws64 for this purpose, the inclination of all set screws 100, or of anylesser number thereof, if desired, to the unit axes (Fig. 6) must underthe circumstances be such that the aforementioned adjustment forces F1and F2 are greater than the frictional resistance encountered by thechuck unit and adapter unit on each other by virtue of the clampingforces exerted on the same by the holdihg screws 64 and theaforementioned additive binding forces F3 and F4, as otherwise the chuckunit would bind on the adapter unit on manipulation of the loosened setscrews for an intended adjustment of the chuck unit. This is readilyaccomplished by arranging the axis-inclined set screws 100 (Fig. 6) sothat their above-described angle formation A (Fig. 6B) are more than 45degrees, and preferably considerably more than 45 degrees.

Those set screws, either all of them or a lesser number, as desired,which on tightening are to augment the axial clamping force exerted bythe holding screws 64 on the units U and 18, are preferably identicallyinclined to the unit axes (Fig. 6) so that, with the holding screws 64tightened to clamp the chuck unit to the adapter unit with reasonablefirmness, the loosened set screws will on manipulation shift the chuckunit on the adapter unit without undue effort despite the ever-presentbinding forces F3 and F4 which, however, are of small magnitude whileadjustment of the chuck unit by some of the set screws takes place andis not opposed by the other set screws. However, as further adjustmentof the chuck unit on the adapter unit is being opposed by any of the setscrews on manipulation of another set screw or screws,

10 as may occur instep-by-step inching of the chuck unit toward its newposition on the adapter unit and will in any event occur on concludingthe adjustment of the former and tightening all set screws, theaforementioned binding forces F3 and F4 will increase rapidly andsufficiently augment the clamping force exerted by the holding screws 64on the units U and 18 to transmit most, if not all, operationalstresses, save substantial torsional stresses, from the chuck unitdirectly to the adapter unit rather than by way of the balls 102 and setscrews 100.

The inclination of the set screws to the chuck axis for the purpose ofaugmenting the axial clamping force exerted by the holding screws on thechuck and adapter units of a chuck of this general type is shown anddescribed in a copending application of Edward A. Galler, Serial No.618,167, filed June 27, 1955. However, the instant set screws 1% whichare inclined to the chuck axis (Fig. 6) are further disposed so thattheir axes pass the respective unit axis on the side thereof (Fig. 3).Hence, the instant axis-inclined and axis-passing set screws (Figs. 3and 6) have not only the same function as those of Galler, to wit, toaugment the axial clamping force exerted by the holding screws on thechuck and adapter units, but have the additional function, foreign toGallers set screws, of locking the chuck and adapter units to each otheragainst relative rotation on relative rotational tendencies betweenthese units.

While the axis-inclined and axis-passing set screws have in Fig. 6 beendemonstrated on a chuck having the advantageous ball links 102 betweenthe set screws in one unit and the other unit, it is fully within thepurview of the present invention to apply these same set screws to anyother conventional universal chuck of the center-adjustable type. Thus,Fig. 7 shows a chuck the adapter unit 142 of which is devoid of balllinks, and instead is provided with a frusto-conical formation 144 withwhich the axis-inclined and axis-passing set screws 146 in the chuck.

unit 148 cooperate.

The invention may be carried out in other specific ways than thoseherein set forth without departing from the spirit and essentialcharacteristics of the invention,.

and the present embodiments are, therefore, to. be considered in allrespects as illustrative and not restrictive, and all changes comingwithin the meaning and equiva: intended to be lency range of theappended claims are embraced therein.

What is claimed is: 1. In a universal chuck of theadjustable type havinga chuck unit with a longitudinal axis and an adapter unit havingprovisions for its attachment to a'support and carrying said chuck unitfor limited relative sliding movement thereon in any direction in aplane normal to said' axis, the combination of surfaces on one of saidunits angularly spaced and extending circularly about a common axisparallel to said unit axis; and a plurality of set screws in the otherunit turnable to cooperate with said surfaces, respectively, foradjusting said chuck unit on said adapter unit, at least one of said setscrews being disposed with its axis passing said common axis on one sidethereof in any adjusted position of said chuck unit on said adapterunit, so that said one set screw and cooperating Surface act wedge-liketo lock said units against relative rotation on rotational tendencies ofeither unit in one direction relative to the other unit.

2. The combination in a universal chuck of the adjustable type as setforth in claim 1, in which at least another of said set screws isdisposed with its axis passing said common axis on a side thereof in anyadjusted position of said chuck unit on said adapter unit, so that saidother set screw and cooperating surface act wedge-like to lock saidunits against relative rotation on rotational tendencies of either unitrelative to the other unit in a direction opposite to said onedirection.

3. In a universal chuck of the center-adjustable type having a chuckunit with a longitudinal center axis and ail-adapter unit havingpr-ovisionsforitsattachment to a supportand carry-ingsaidchuck*unit"-for"1imited' relative slidingmovement thereon in any directionin-aplane normal to said-axis, thecombinationof-surfacesmmone of saiduni-ts angula-rly "spaced and extending circularly about a commonaxisparalleltosaidunitaxis; and a pluralityofrsetscrews in the other-unitturnable tocoopera-te with said'surfaces;respeetively,-' for-adjustingsaid chuck unit on' said adapter :uhi-tysaid-setscrews beingdisposedwit-h-their'aXes lying in acommonplane normal to'either-axis,--and at leastone-Ofsaid set screws being disposed with its axispassing said-common axis-on'one side thereofinanyadjustedpositionofsaidchuck unit on said adapter unit,-so'that saidone-set screwand cooperating surface act wedge-like to locksaidunitsagainst relative rotation on rotational tendencies of either unitinone direction relative to the otherunit.

4.' The combination in a-universal chuck of the centeradjustable type-assetfor-th inclaim 3, -in which atleast another ofsaid'set screwsisdisposed with its axis passing said common-axis on-asidethereof in anyadjusted position of said chuck-unit onsaid adapter unit, so that-saido'ther set screw and cooperating surface-act wedge-like tolock saidunits against-relative rotation onrotational tendencies o'f either unitrelative to the other 'unit-in-a direction opposite to said onedirection.

5. In a universal chuck-ofthe center-adjusta'ble-type having aehuckur'r'it with a longitudinal center 'axis and an adapter unit having"provisions for its attachment to a support andcarrying saidchuck unit'for limited relative sliding movement thereon inany diI'CCtiQHiIJ2fP13HGnormal to said axis, the combination of frusto-conical surface parts=orr one of'said units angularly spaced and extending circularly aboutacommon axisparallel to said unitax is; and-aplurality of set screwsin-tbe other unit turna'ble-to cooperate-with said surface parts;respectively, foradjustingsaid chuck unit on said adapter unit; at leastone of said set screws being disposed so that itsaxis not onlypassessaid-common axis on one side thereof in any adjusted position ofsaid chuck unit on saidadapter unit, butalsojliesdn aplane whichextendstransversely of and inclined to said ;unit axis andforms with thelatter an acute angle pointing oppositeto the axial direction in whichsaidfrusto-conical surfaceparts decrease injdiameter, whereby said oneset screw and cooperating surface part act wedge-like to lock saiduni-,ts againstrrelative rotation on.rotatinnaltendencies of eithenunitin one direction relativ t the other .unit, :an ialsosaxially doclamprsaidlunits together, respectively.

.16. I erCQmbina'tiQn in allmiversal chuckof the ,centeradjustable type,as, set forth in-rclaim 5,. in .which rat. least another ofsaidisetscrews-is=disposed-witli its axispassing said common axison-asidethereof-in anyadjnstedpo'sition of said' chuclounit -onsaid-"adapter nnin'so that said other set-- screw -=an,cl cooperatingsurfacepart act-"wedgelike rto' lock said units against relativerotationon--r0tat'iona'li tendencies eteither unit-rela-tive to,theother unit in-a direction opposite to said one-direction.

"7. I a universal chuck of the adjustable type'jhaving a-chuck-*unitwith afirst longitudinal center aX'is" and-an adapter I unit 'withN a longitudinal center axis parallel to said Efirst axis 'and= having;provisions for its attachment to a :support' and carrying said chucktunitfjfor limited relative sliding-movement thereonin: any .directionin' a plane normal to saidaxes; the combinationof a plurality of'sockeis in one unit angnia'rlyspaced about thecenter axis :ofthe-latter; ballslseated' and tumble in said sockets,respectivelypandsetgscrews in*the;other unit engaging withtheir endsurfaces said balls, respectively, and being turnable-Efor adjustingsaid1c-hu'ck unit -on said adapter unit,- ea'ch of saidballs havinga3flat and saidend surfaces of' said 1set'screws being flat and engagingthe flats on the "respective balls,;an'd atleast .i one of..said..setscrews beingdi sposed with its-axis passing said center axis of saidone-unit on one sideithereof inany adjustedpositionof said chuck 'unit'on saida'dapter unit,so that said one set SCI'BWf'fiEid 'ball engagedthereby act wedge-like to lock said unitsagainst relative rotation onrotational-tendencies of-either:unitin'onedirection relative to .theother unit.

"8.Thecombination in -a universalchuck of the.adjustable type;as'set-forth inclaim' 7 in which at; least another'of said-set screwsis'dispose'dlwith' its axis passing'said-centeraxis'of said one unit ona side 'thereofin anyadjusted position of said chuck unit on saidadapter unit,- so that said other set screw and ball engaged thereby actwedge-iike to lock said units against relatives rotation on-rqtationaltendencies of either .unitrelative' to (the other unitin adirectionopposite to said one direction.

"9.The combination in a universal chuck of the adiustable type as setforth in c1aim7,. in which said one set screw is so disposed that itsaxis alsolliesinaplane which extends transversely of and inclined toeitherccnter axis and formstherewith an acute angle, whereby. said-onesetiscrew and ball engaged thereby alsonactnaxia ly clamp said unitstogether.

References Cited in 'the -file of this patent Z'UNITED STATESTATENTS

